High-frequency heating
When electromagnetic waves of appropriate frequency are beamed into the plasma, energy is imparted to the plasma particles by the wave field and passed on to the other particles through collisions – „microwave oven“ principle. The gyration of the ions and electrons around the magnetic field lines afford suitable resonances. The gyration frequency of the ions is between 10 and 100 megahertz, that of the lighter electrons between 60 and 150 gigahertz.